Bobby Crawford, who plays the schoolboy who delivers a message to the McCain ranch, is Johnny Crawford's brother both being the sons of the film editor Robert Crawford, Sr. All three were Emmy nominated in 1959. In1965 all three were involved in the film 'Indian Paint', the sons were actors and the father was a producer. Bobby matched his brother when he got a regular role in another Western series, 'Laramie'.
It is established here that Lucas and Mark lived in Claypool ,Wyoming before coming to North Fork.
One of only two episodes that Paul Fix as Marshal Micah Torrance appears in the show, but is not listed in the credits: Smoke Screen (1960) & Eight Hours to Die (1958).